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Discussion Starter · #1 ·
I have a 65 389 which has less than 2k miles since complete rebuild. I believe Jim Mott did the rebuild. It has a Howards cam with the 068 profile, stock rockers a short polylocks. I have adjusted this valve train until I was blue in the face, and finally succumbed to a hot/running adjustment. What I found was a couple of the valves can be adjusted to quiet, but then within 30 seconds become noisy again. This happens sporadically sometimes quiet then clacking then quiet.
The engine runs extremely strong, oil pressure is 40-50 at idle.

I suspect I have a couple bad lifters and have decided to replace them all. This is the issue, I wanted to buy a set of Johnson lifters through Butler, but they are on indefinite backorder. What brand and source would you guys recommend?
Please no cheap off shore stuff!

Thank you in advance!
 

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I have a 65 389 which has less than 2k miles since complete rebuild. I believe Jim Mott did the rebuild. It has a Howards cam with the 068 profile, stock rockers a short polylocks. I have adjusted this valve train until I was blue in the face, and finally succumbed to a hot/running adjustment. What I found was a couple of the valves can be adjusted to quiet, but then within 30 seconds become noisy again. This happens sporadically sometimes quiet then clacking then quiet.
The engine runs extremely strong, oil pressure is 40-50 at idle.

I suspect I have a couple bad lifters and have decided to replace them all. This is the issue, I wanted to buy a set of Johnson lifters through Butler, but they are on indefinite backorder. What brand and source would you guys recommend?
Please no cheap off shore stuff!

Thank you in advance!
Both sides of the engine or just on one side?

You say stock rockers, does that include the stock bottleneck rocker arm studs? If so, you may be bottoming the polylock on the rocker arm stud shoulder - just like the factory nut would do. You want the 7/16" big block rocker arm studs so you can adjust the polylock all the way down as needed. You other option is to put hardened washers under the polylock to give you more adjustment before it hits the factory rocker stud shoulder.

Have you checked your rocker arm contact area at the valve stem? Rebuilt can mean deck milling and head milling - both of which can cause pushrod length to change, and thus, rocker arm geometry. You may also have the incorrect length pushrods if somewhere along the way they were ever changed out.

What oil type and weight? Oil type and weight can affect the bleed down rate of the hydraulic lifter.

Could be a bad cam if the cam was not broken in correctly.

Check a few things first before tearing into the engine.

Try Nitemare Performance and see if he has a set or recommendation if you get to that point.
 

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Discussion Starter · #3 ·
Thanks for the reply Jim. To answer some of your questions;
The poly locks are the short style and offer alot of adjustment. I have not experiencing them bottoming out.
The rocker arm contact with the valve stem look centered. I also dont see any significant difference with rocker arm travel when running.
I am using 20-50 Brad Penn semi-synthetic, PF 24 filter.
When adjusting the valves running it really doesn't 'shoot' oil out of the rockers but more like dribbles oil out through the rockers. The rockers have plenty of oil in them when I pull the valve covers.
.
 

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Thanks for the reply Jim. To answer some of your questions;
The poly locks are the short style and offer alot of adjustment. I have not experiencing them bottoming out.
The rocker arm contact with the valve stem look centered. I also dont see any significant difference with rocker arm travel when running.
I am using 20-50 Brad Penn semi-synthetic, PF 24 filter.
When adjusting the valves running it really doesn't 'shoot' oil out of the rockers but more like dribbles oil out through the rockers. The rockers have plenty of oil in them when I pull the valve covers.
.
20W-50 is too thick. 15W-40 would be as thick as I would use. 10W-30 is factory stock. I might also try a standard petroleum based oil, and not the semi-synthetic. Try a Wix filter, or NAPA Gold as they are pretty good filters - and may flow a little better.

Oil dribbling out the rockers sounds suspicious. Could be the thicker oil, BUT, could be that the wrong lifters were used and the oil band could be dropping too low in the lifter bores and releasing oil pressure. Some mistakenly use the Chevy lifters when rebuilding a Pontiac and this is what happens.

Oil will also dribble if the rocker arms are too tight. You should observe the pushrods spinning with the engine running. This also is an indicator that the lifter is spinning correctly on the cam and not just sitting on the lobe and wearing it down.

Put a dab of white paint, or something, on the top section of the pushrod where you can see it. Run the engine and you want to see that white spot spinning. It should be spinning at idle, but sometimes a little more RPM will do it.

If you do not see the pushrod spinning, it could be too tight, so back the polylock off until you do see it spinning. Then you can go back down if needed, but do not go too tight until is stops spinning. If you cannot get the pushrod to spin after backing off the polylock, then you may have a bad lobe/lifter.

Some lifters will clatter by design like the Rhoads or what some call "anti-pump up" lifters which are designed for higher RPM's. So an email or call to the lifter manufacturer can confirm this as well.

You could also have an oiling issue one of the oil galley plugs was left out in the back of the block or leaking. A good sign of this is oiling on only one side of the rockers. I believe the dirvers side will see some oil and the passenger side will be diminished.

Again, do some more investigating and try a few things before pulling the intake. You may still have to do this just to check things out. Just watch that oil pressure. The Pontiac 60 PSI pump was rated 60PSI @ 2,600 RPM's. If you use thinner oil, your idle oil pressure may go down some, which is normal. 40-50 psi at idle in my book is a little high if 60 PSI oil pump unless an 80 PSI oil pump was installed instead.
 

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Discussion Starter · #5 ·
again Jim thank you for the replies. I will go through your recommendations and see what develops. It may be a couple weeks before I get to it but I will report back.
all the best, Steve
 

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Discussion Starter · #7 ·
UPDATE; I have followed some of the advice here, with little positive results. I have changed the oil filter to NAPA, changed oil to Rotella T5 15-40. Marked the pushrods with white paint dot, yes they are rotating. I am going to try to post a video so you can see what I am talking about.
The valves are adjusted hot/running at zero lash plus 1/2 turn. I even tried 3/4 but did not make a difference.

link: October 20, 2021
 

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UPDATE; I have followed some of the advice here, with little positive results. I have changed the oil filter to NAPA, changed oil to Rotella T5 15-40. Marked the pushrods with white paint dot, yes they are rotating. I am going to try to post a video so you can see what I am talking about.
The valves are adjusted hot/running at zero lash plus 1/2 turn. I even tried 3/4 but did not make a difference.

link: October 20, 2021

First, OK on the NAPA filter, but I believe the Rotella T5 is synthetic. It is the T4 that is old school oil. But from what I read, many of the synthetics have been reformulated from the earlier oils and can be used with the older engines.

Watched the video. It appears that the front couple of rockers are getting a good amount of oil and then looking down the line, I'm not seeing quite the same flow?

Are you sure you have good oil pressure? Did you try bring RPM's up a little to observe the oil flow? Often with the valve covers off, oil will be squirting about making a bigger mess than what you have. There are 3 different oil pressure ratings used by Pontiac, 40 PSI for the big cars and low performance cars, the 60 PSI for GTO's and high performance engines, and the 80 PSI used by the SD engines. These PSI ratings are at 2,600 RPM's per the factory specs.

Pushrods spinning is typically a good sign.

So what you are saying is that you have backed off the poly lock until you hear the lifter noise/clicking. Then you tightened the poly lock until the clicking stopped. Then you waited for the lifter to "normalize" (which is bleed down) which should be about 10-15 seconds and listened for clicking. If it clicks, you tighten down again until clicking stops, and let the lifter "normalize". You repeat this process until no more clicking is heard. At that point, you tighten the poly lock 1/4 turn and lock it down.

It sounds like a bunch of your lifters are clicking, so make sure you adjust them correctly as above.

The '65 rocker arm studs are stock press-in studs.

So why are you using the poly locks?

Why not use the factory rocker arm nuts and torque them down to 20-25 foot pounds? You might want to get a set and put them on 1 pair of rocker arms that are clattering just to see if that does it.

The poly locks may be too short and you are not getting the rocker arm ball down far enough on the rocker arm stud.

I would also make sure you have the correct length pushrods for your engine. Pontiac did use different lengths and then you can get aftermarket in several lengths. Unless you know the engine was never apart in it's lifetime and the machine shop didn't err on pushrod length, then I would at least pull 1 pushrod and measure it to confirm you have what your engine needs. If they are too short, then you may have an issue - just another thing to check/verify.

If none of that works, then it may be time to pull the intake and remove/verify that the lifters are good and that you have Pontiac specific lifters and not Chevy lifters.

Hopefully others will look at the video with their observations.
 

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Discussion Starter · #9 ·
Jim, thanks once again for your detailed reply.
Yes I used Rotella T4, non synthetic. (my typo)
The engine was built by Jim Mott (GTO expert?) a couple of years ago. I have the cam card but know little else about what was done other than .30 over, standard crank, and valve job.
I didn't trust the stock oil pressure gauge so I installed a SW mechanical which is feed from a T fitting near the original sender. It reads 45 lbs at idle and will peg at 60lbs at speed.
I too was surprised that I didn't have a bigger mess adjusting the valves with the engine running. I did idle the egine way down to around 550rpm for this procedure.
I read your adjusting procedure, and did not wait for the lifters to bleed down as you noted. I will try that.
I am going to buy some stock crimp style locknuts and try those as I don't feel the cam and spring rates are radical which would preclude using those.
I will also check the pushrod length. I believe these should be 8.250?

All said, other than the noise this 389 runs extremely strong. You really have to get after the shifting when the tripower kicks in, (3:90 rear gear). It will rev to 6000 rpm quickly.

To be continued,,,,,,
 

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So on the same subject I notice some lifter or rocker clicking when the motor starts up mostly sounds like from the driver's side and takes until it's to temperature about 180° to seem to go away and not completely, but I haven't really documented it. This winter I changed to Scorpion 1.65 Race rockers, it's an all roller valve train assembled by Butler, also used Rotella 15W40 T4 which helped quiet it down some. I have around 80+ psi cold at idle and maybe 20 psi when hot going up with rpms like it should on the dash gauge and remote gauge under the hood teed into the oil filter housing. I followed Scorpion and Butler's directions installing the rockers, turning the motor over by hand until the exhaust pushrod starts to move open then installing the intake rocker so the pushrod has no slack (zero lash) then tighten the poly lock down 5/8" -3/4" turn then lock down the set screw then bumping the nut and screw a hair tighter together all doing this cold. I did run it with the valve covers off and was getting oil out of all the rockers and push rods wouldn't be rotating on a roller set up I don't think right?
 

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So on the same subject I notice some lifter or rocker clicking when the motor starts up mostly sounds like from the driver's side and takes until it's to temperature about 180° to seem to go away and not completely, but I haven't really documented it. This winter I changed to Scorpion 1.65 Race rockers, it's an all roller valve train assembled by Butler, also used Rotella 15W40 T4 which helped quiet it down some. I have around 80+ psi cold at idle and maybe 20 psi when hot going up with rpms like it should on the dash gauge and remote gauge under the hood teed into the oil filter housing. I followed Scorpion and Butler's directions installing the rockers, turning the motor over by hand until the exhaust pushrod starts to move open then installing the intake rocker so the pushrod has no slack (zero lash) then tighten the poly lock down 5/8" -3/4" turn then lock down the set screw then bumping the nut and screw a hair tighter together all doing this cold. I did run it with the valve covers off and was getting oil out of all the rockers and push rods wouldn't be rotating on a roller set up I don't think right?
Yes, no rotation from the pushrods as the roller lifters ride on the roller base that makes contact with the cam lobe. If they are rotating - you are in big trouble. (y)
Jim, thanks once again for your detailed reply.
Yes I used Rotella T4, non synthetic. (my typo)
The engine was built by Jim Mott (GTO expert?) a couple of years ago. I have the cam card but know little else about what was done other than .30 over, standard crank, and valve job.
I didn't trust the stock oil pressure gauge so I installed a SW mechanical which is feed from a T fitting near the original sender. It reads 45 lbs at idle and will peg at 60lbs at speed.
I too was surprised that I didn't have a bigger mess adjusting the valves with the engine running. I did idle the egine way down to around 550rpm for this procedure.
I read your adjusting procedure, and did not wait for the lifters to bleed down as you noted. I will try that.
I am going to buy some stock crimp style locknuts and try those as I don't feel the cam and spring rates are radical which would preclude using those.
I will also check the pushrod length. I believe these should be 8.250?

All said, other than the noise this 389 runs extremely strong. You really have to get after the shifting when the tripower kicks in, (3:90 rear gear). It will rev to 6000 rpm quickly.

To be continued,,,,,,

Butler lists the stock pushrods as 8.715" which I also verified through my HO Enterprises parts spec booklet 1961 through early 1967. They also have the "ball" type end.

The 1967 GTO & GP, and 1968 to 1979 400CI engines are listed as using the 9.145" length.

The RAII pushrod is listed as 9.137"

 

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Yes, no rotation from the pushrods as the roller lifters ride on the roller base that makes contact with the cam lobe. If they are rotating - you are in big trouble. (y)



Butler lists the stock pushrods as 8.715" which I also verified through my HO Enterprises parts spec booklet 1961 through early 1967. They also have the "ball" type end.

The 1967 GTO & GP, and 1968 to 1979 400CI engines are listed as using the 9.145" length.

The RAII pushrod is listed as 9.137"

So what about the clicking until it's up to temperature is that a roller valve train trait or should the valves be adjusted hot or should I not worry about it and turn the radio up?
 

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So what about the clicking until it's up to temperature is that a roller valve train trait or should the valves be adjusted hot or should I not worry about it and turn the radio up?
From what I have read over at the PY site and other forums on the roller lifters, seems some of the lifters are indeed noisier than others depending on manufacturer. If they are solids, then my understanding is you would lash them like flat tappet - which is hot. If hydraulics, then I would "zero lash" them.

There was member on here in the past and his made a lot of ticking noise. He went with a different weight of oil and that improved them quite a bit. Seeing it clears up after it warms up, that may indicate an oil that is too thick when cold.

Seeing it is a Butler build, you may want to ask them what they suggest.
 

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Ok so I did the rocker install correctly? I was running 20W50 because that's what Butler used then switched to 10W30 or 40 when I read that was to heavy then saw here that 15W40 was a good choice so I'm using that, not a big deal just making sure I didn't do anything wrong when I read about other people's issues 👍
 
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